NASA spacecraft detects ice and organic compounds on Mercury

NASA spacecraftdetectsice andorganic compoundson Mercury ﻿

Monday, Dec. 17, 2012

by Claiton Zanini Brusamarello, M.Sc.﻿

Despite the hot daytime temperatures, Mercury, the closest planet to the Sun, has frozen ice and organic compounds inside craters that are permanently shadowed in its North Pole, NASA scientists said on Thursday, Nov 29. 20 years ago, telescopes on Earth gathered evidence of ice on Mercury, but the discovery of organic substances was a surprise, according to researchers working with NASA’s Messenger spacecraft, the first spacecraft to orbit the planet.

Scientists believe that the ice and organic compounds, which are similar to tar or coal, fell to the planet millions of years ago aboard comets and asteroids.

"It's not something we expected to see, but then of course you realize that it kind of makes sense because we see it in other places, as the icy bodies of the outer solar system, and in the nuclei of comets.” said David Page, planetary scientist of the University of California, Los Angeles.

Unlike NASA’s probe Curiosity, which is directly examining samples of Martian rocks and soil to search for organic compounds, Messenger emits laser beams, to count particles, measures gamma radiation and collects other data remotely as it orbits the planet.

The discovery of ice and organic compounds on Mercury is based on computer modeling and laboratory experiments, which took more than a year, but not by direct analysis.

"The explanation that seems to fit all the data is that it is organic material," said Messenger chief scientist Sean Solomon of Columbia University in New York. Paige added that "there is only a crazy hypothesis - nobody got anything that seems to fit the observations best."

The idea of ​​having organic chemistry on Mercury was so remote that Messenger had few of the standard sterilization procedures adopted to minimize the chance that terrestrial bacteria would contaminate any local material with the capacity to generate life.

Life on Earth is based on organic compounds, but not all organic compounds are necessarily associated with life. Scientists do not believe that Mercury is or has ever been suitable for life, but the discovery of organic compounds on an inner planet of the solar system can reveal how life began on Earth and how it might evolve on other planets outside our solar system.

The findings were published in this week's edition of the journal "Science."